Wal-Mart has been a leader in using information technology to reduce costs. A huge part of succeeding in retailing is to provide the right products in the stores at the right price, when customers want to buy them. To succeed, Wal-Mart needs to forecast demand for every product in every store. Each product can have multiple variations—such as size or color. Individual items are commonly identified with an SKU number (stock-keeping unit), pronounced “skew.”